Field of the Invention
The invention pertains to the field of rotary cutting tools. More particularly, the invention pertains to an end mill and a method of manufacturing the end mill using laser radiation to produce and process a billet made of Superhard material, such as Cubic Boron Nitride (CBN), Polycrystalline Cubic Boron Nitride (PCBN), Polycrystalline Diamonds (PCD), tungsten carbide (WC), and the like.
Description of Related Art
Cubic boron nitride or c-BN was first synthesized in 1957 by Robert H. Wentorf at General Electric, shortly after the synthesis of diamond. Cubic boron nitride is insoluble in iron, nickel, and related alloys at high temperatures, but it binds well with metals due to formation of interlayers of metal borides and nitrides. It is also insoluble in most acids, but is soluble in alkaline molten salts and nitrides, such as LiOH, KOH, NaOH/Na2CO3, NaNO3 which are used to etch c-BN. Because of its stability with heat and metals, c-BN surpasses diamond in mechanical applications. The thermal conductivity of BN is among the highest of all electric insulators. In addition, c-BN consists of only light elements and has low X-ray absorptivity, capable of reducing the X-ray absorption background. With great chemical and mechanical robustness, c-BN has wide applications as abrasives, cutting tools, and even one of the popular X-ray membranes.
It is desirable to manufacture a micro cutting tool with a cutting tip made of Superhard material, such as c-BN or polycrystalline cubic boron nitride (PCBN). However, it is currently highly challenging to efficiently to manufacture a micro cutting tool having a cutting tip made of Superhard material because of the extremely small cutting diameter of between about 0.5 mm to about 10 mm.
Accordingly, there is a need in the art for an improved cutting tool, and in particular a micro cutting tool with a cutting tip with an extremely small cutting diameter that is made of a Superhard material.